Manchester United have now scored 18 times in four pre-season matches in the United States and while the standard of opposition may not be the most challenging, Sir Alex Ferguson is still entitled to be encouraged by the frequency with which his team have demonstrated the imbalance of talent.

This was another impressive performance from the Premier League champions, Anderson and Park Ji-sung putting them 2-0 ahead at the interval before Dimitar Berbatov and the substitute Danny Welbeck completed the rout in the second half.

It was Berbatov's first goal of their tour and, after the trauma of not even getting on the substitutes' bench for the Champions League final, it was noticeable that Sir Alex Ferguson made a point of greeting him warmly when he was taken off just over an hour into the match.

Ferguson used 20 players in total – only Phil Jones and Patrice Evra lasted the full match – but there was a clear gulf between the two sides despite all the experimentation, particularly once Anderson had opened the scoring in the 20th minute.

Jones, the new £16m signing from Blackburn Rovers, had a relatively trouble-free evening and Anders Lindegaard can also reflect on a satisfactory 45-minute display, demonstrating once again that he has legitimate credentials to challenge David de Gea, the £18.3m recruit from Atlético Madrid, to be known as United's first-choice goalkeeper next season. Lindegaard, who made way for Ben Amos at half-time, has had an impressive tour and looked assured behind a defence in which Jones, a centre-half by trade, started at right-back.

Jones coped ably with the sporadic threat of Thierry Henry during the former Arsenal player's 45 minutes on the pitch. Ashley Young, another of United's new signings, flickered only sporadically but, overall, there was plenty to satisfy Ferguson on a night when Wayne Rooney set up two of the goals and his team demonstrated a ruthlessness in attack.

That Anderson scored the first will also be encouraging for Ferguson because it is undoubtedly time the Brazilian improved on his record of a mere five goals in 129 appearances. Anderson has run the danger at times of becoming synonymous with poor finishing but on this occasion it would have been almost impudent to miss the chance that Rooney teed up for him after a neat exchange of passes with Berbatov.

Park's third goal in four pre-season matches was more of a solo effort, the South Korean taking the ball from Evra on the left-hand corner of the penalty area, turning past the right-back, Sean Franklin, to score with a left-foot, diagonal shot combining equal measures of power and precision.

The more dangerous moments concocted by the MLS team invariably stemmed from the right boot of David Beckham, whose passing was sublime during the opening half. It was a stylish display from the former England captain, but it was also a hot and humid evening and he faded after the restart, with United taking control.

Berbatov's goal stemmed from a carefully weighted through ball from Rooney, the Bulgarian holding off the nearest defender, Geoff Cameron, before lobbing the goalkeeper, Tally Hall. The ball came back off the crossbar but Berbatov was first to the rebound, turning in his shot from six yards.

Welbeck, one of six substitutes introduced in the 61st minute, then scored the fourth when he darted in from the left and lashed in a right-foot shot that took a decisive deflection off Cameron to wrong-foot Hall.

Ferguson rested De Gea, Ryan Giggs and Rafael da Silva while Javier Hernández was left at the team hotel after being concussed during a training session in the stadium on Tuesday, the Mexican spending the night in hospital for precautionary tests.